Device for inspecting and recording the appearance of threads and yarns



July 3, 1 F. H. GERMANS ETAL DEVICE FOR INSPECTING AND RECORDING THE APPEARANCE OF THREADS AND YARNS Filed Feb. 15, 1952 Patented July 3, 1956 DEVICE FOR INSPECTING AND RECURDIWG THE APPEARANCE F THREADS AND YARNS Fedde Hendrik Germans, Enschede, and Willem Voogt,

Borne, Netherlands, assignors to De Nederlandse 0rganisatie Voor Toegepast-Natuurwetenschappelijk Gnderzoek Ten Behsoeve Van Nijverheid, Handel en Verkeer, The Hague, Netherlands, a corporation of the Netherlands Application February 15, 1952, Serial No. 271,838

1 Claim. (Cl. 73-160) This invention relates to the inspection and photographing of threads or yarns whereby a record of the appearance thereof may be obtained.

For the purpose of inspecting the appearance of threads and yarns, these yarns are Wound on black boards. As a rule the distance between the windings varies with the counting number of the yarn.

An inspecting method, commonly used, divides all yarns in five classes or groups, in relation to their counting number. definite number of turns per inch for the purpose of inspecting the appearance. This method permits comparison of the wound yarn with a standard sample or a photoprint of a standard sample. The inspecting of the appearance in this way is of special importance because interference, caused by periodicity in the thickness variations of the yarn, is easily perceived.

To wind the yarn, the board is usually rotated while the yarn is conducted by a yarn guide, moved by a screw spindle parallel with the rotation axis of the board, this yarn guide thus controlling the number of turns per inch of the yarn on the black board.

With another known apparatus the yarn is wound on a black cardboard, fixed on a rotating cylinder with a number of turns per inch as prescribed by the class of the yarn, after which the card board with the yarn is removed from the cylinder and flattened.

The yarns are usually classified in the following five groups depending on the yarn counts:

In both methods adhesives are sometimes applied to the board or card board, or to the yarn itself, to prevent displacement of the yarn on the board. Nevertheless, during the Winding or subsequent handling of the yarn on the board, it is not possible to prevent displacement of the yarn, said displacement causing irregularities in the number of turns per inch. It is not possible to inspect the appearance of a yarn with an irregular number of turns per inch, because interference, caused by periodicity in size variations, cannot be perceived. This drawback is very serious, when samples on board have to be kept for comparison purposes or subsequent inspection.

The object of the invention is to provide a device with which in an easy way accurate photographic records of the appearance of yarns can be made, which will not be changed on handling, and which device enables one to make as many identical photographic records of a sample as desired, these records permitting an accurate inspection of the appearance of the yarn, because no deviations will For each class it is prescribed to wind a occur in the prescribed distance between the parallel parts of the yarn.

The device according to the invention comprises a frame, two cylinders, each provided with equidistant circular grooves of identical profile, and rotatably mounted on said frame in parallel and spaced relationship, a support between said cylinders for a printing frame for photosensitive material to locate the upper surface of said material substantially in the plane tangent to the bottoms of the grooves on the two cylinders, and a printing frame adapted to be located on said support.

A driving device, preferably with variable speed, may be used to rotate one or both of the cylinders for automatical replacing of the yarn, which has been insepected, by another yarn which is to be inspected. In order to do so the yarn wound on said cylinders and inspected is not removed but the beginning of the new yarn to be inspected is tied to the end of the yarn wound on the cylinders, so that after a given number of revolutions the new yarn is automatically wound on the device. A yarn tensioner may be provided with advantage so that the winding of the yarn is carried out under constant tension. This yarn tensioner known in itself is preferably of a type that permits control of the tension, so that it is possible to choose different tensions according to the counting number of the yarn to be inspected.

To use the device for yarns of various classes, we prefer to mount the cylinders at one side rotatably in a common frame which can be removed together with the cylinders, the opposite ends of the cylinders being ro tatably on or within supports from which they can be easily removed. By providing five sets of cylinders, each set being mounted on an individual common frame and having per inch on their lengths a number of grooves corresponding with the number of turns per inch prescribed for one of the five classes, as set out above, it is possible to cover the entire field.

The invention will be explained more in detail in connection with the accompanying drawing which shows an embodiment of the device partly in elevation and partly in section.

The device comprises a frame 106 rotatably supporting two cylinders 187 and 198. The cylinders are provided with blind bores and slipped on the spindles 109, 110 respectively, the first of which is supported in a bearing 113, the second one in an auxiliary frame 112, mounted on the frame 106. The spindle 110 is driven by an electromotor 114 through the intcrmediance of a train of gears located Within the auxiliary frame 112. The key 111 provides a connection between said spindle and the cylinder 108. The cylinders 107, 108 are provided at their front ends (not shown in the drawing) with journals rotatably mounted in a second frame which is fixed to the main frame 1% and can be removed together with the two cylinders 1d? and 108 which, as has already been set out above, are slidably mounted on their respective spindles 109, 110.

The frame 1% is provided with a bushing 117 carrying a pin 113 which is fixed to a support 120; said support is located between the cylinders and serves to hold against the threads the printing frame 104 provided with a sheet of photosensitive material 105. This bushing is positioned near the ends of the cylinders which are opposed to the second frame so as not to impede the removal of said frame together with the cylinders 107, 108 with the yarn wound over them. A helical compression spring 119 is positioned around the pin 118 between the upper surface of the bushing 117 and the lower surface of the frame 120, so as to press the photosensitive material against the yarn. A ring 134 is provided on the pin to limit its movement in the upward direction so as to prevent excessive pressure between the photosensitive mathe: electromotor 1'14 by meansof the gear train located in the auxiliary casing 112. The cylinder 130 is pivo tably: mounted on the auxiliary frame 112 and provides the necessary pressure to entrain the yarn. The velocity ofi thecylinden 129 is-higher than that ofthe cylinder 108 so. that a certain amount ofslip occurs between the yarn and the cylinder 129. to prevent the grooving of the cylinder 129 due to wear, the position of the yarn with respect to said cylinder is continually varied by the guide 131 to which a reciprocatingmovement is imparted.

It will be understood that various other embodiments are possible without departing from the scope of the invention.

What; we claim is:

In a device for inspection of threads and yarns comprising a supporting frame, a pair of cylinders rotatably mounted thereon in parallel and spaced relationship and having equidistant circumferential grooves arranged along 4, is adapted to be wound around the cylinders and in the grooves soas to form an upper anda lower row of parallel threads or yarns, a printing frame positioned parallel with the rows of thread between said cylinders and adapted to have a sheet t photosensitive material disposed on said printing frame and spring means acting on said printing; frame; to; apply said;sl 1 eet against the lower e nc s iited' th file. f. thi p t UNITED, STATES, BATENTS' 904,310 Cole Nov. 17, 1908 03 09 ichael sn May 6 9 9 1,441,635 Rived Jan. 9, 1923 1,505,127 Ayres- Aug. 19, 1924 2,037,044 Reinartz et a1. Apr. 14, 1936 2,052,711 leanings Sept. 1, 1936 2,471,362 Vin May- 24, 1949 2,490,134 Jennings Dec. 6,- 1949 2,592,039; Laetsqh et a1, Apr. 8, 1952 

